New data from Mars is causing scientists to reconsider the origin of a massive crater on the Red Planet.
Studying data from orbiting satellites as well as surface readings from the Mars rover, scientists now believe a huge crater was created by a super volcano rather than an asteroid impact.
According to scientists, the super volcano would have been active during the first billion years of Martian history and that the eruptions would have destroyed the Martian atmosphere.
Similar super volcanoes can be found on Earth underneath Yellowstone National Park, Lake Toba in North Sumatra, Indonesia, and the Canary Islands off the west coast of North Africa.
Such an eruption would have drastically altered the climate on Mars by sending huge amounts of ash and gas into the atmosphere.
The remains of the volcano were spotted in images of the Arabia Terra region of Mars. The terrain is heavily pitted with impact craters, but scientists studying images of a large circular basin called Eden Patera noticed it lacked the typical raised rim and splash marks beyond that come from asteroid strikes.
Instead the 52 mile wide and one mile deep basin had a series of rock ledges similar to bathtub rings that form after a lava lake slowly drains.
The basin is also ringed by faults and valleys that occur when the ground collapses due to activity below.
This led experts to suggest the basin is actually a volcanic caldera that caused when a large body of magma loaded with dissolved gas rose through the thin crust to the surface. This caused the super volcano to blow its contents over a huge area.
“This highly explosive type of eruption is a game-changer, spewing many times more ash and other material than typical, younger Martian volcanoes,” said Dr Jacob Bleacher, a volcano specialist at NASA’s Goddard Space Flight Centre. “During these types of eruptions on Earth, the debris may spread so far through the atmosphere and remain so long that it alters the global temperature for years.”